In the field of construction and, especially instances relating to the plumbing trade, it is common to install a source of potable water on a flat roof. The source is often a water hydrant or bibb that permits maintenance personal to use the water to hose down or wash equipment mounted upon the roofs surface. Such equipment would include roof top air conditioners and exhaust fans that periodically require cleaning in order to assure efficient operation, void of dust and other wind blown debris.
Typically, such roof top water hydrants are installed in a manner that prevents rainwater from entering the building through roof penetrations used to provide the water source to the hydrant. FIGS. 22, 23, and 24 are prior art illustrations of such devices. FIG. 22 shows a freeze resistant hydrant housed within a sheet metal hooded enclosure. The hooded enclosure includes loose insulation around the insulated piping to prevent freezing. The hood is intended to prevent rainwater from penetrating the enclosure. The entire apparatus is mounted to the roof with flashing to prevent leakage at its perimeter.
FIG. 23 is a simple hose bibb type of hydrant that extends through an aperture in a flashing or pitch-pan that is sealed to prevent rainwater from entering the building through the aperture. FIG. 24 shows the use of a common frost-proof post hydrant mounted atop a roofline with the penetration at the roof sealed at a pitch-pan.
All of the above techniques are common in the construction industry and may include various modifications as to height of placement of the hydrant above the roof, the design of the enclosure, or the means used to prevent rainwater from entering the building. Unfortunately, each of the techniques depends on the lack of human error in their installation to assure satisfactory performance. To illustrate and as shown in FIG. 20, the enclosure is typically formed and fitted by an individual. Therefore, the skills and craftsmanship, or lack of skill of the individual, determines if the installation is successful. If the enclosure is poorly made, fitted or sealed, then there is a risk of leakage. If the insulation is not properly installed, then there is the risk of a pipe freezing during colder weather.
As shown In FIG. 24, the watertight seal at the pitch pan is subject to problems simply because the post hydrant extends well above the roofline. For example, while being used, it will be easy to pull and then push the post about with significant leverage, and thereby create potential sources of leakage. Similarly, the hydrant in FIG. 24 may be subject to disruptions of the seal at the pitch pan.